Implementing Arbitrary-Precision Arithmetic Operations in C++

When dealing with integers that exceed the range of standard data types (such as long long), we need arbitrary-precision arithmetic, commonly known as "big integer" operations. This approach processes numbers digit by digit using arrays or strings, handling carries manually to support values of virtually any size. High-Precision Addit ...

Posted on Tue, 13 Oct 2026 16:45:45 +0000 by andre_c

Optimized Bitmask Dynamic Programming for Hamiltonian Path and Circuit

The naive dynamic programming approach for Hamiltonian path and circuit problems typically runs in O(n!) time, or O(2ⁿ n³) using standard bitmask DP. We will optimize this bitmask DP framework to achieve O(2ⁿ n) time complexity and O(2ⁿ) space complexity. The baseline bitmask DP uses the state dp[S][u][v], which denotes whether a path exists fr ...

Posted on Tue, 13 Oct 2026 16:16:18 +0000 by cage

C++ Performance Optimization: Practical Constant-Time Improvements

Understanding Constant-Time Optimizations in C++ The techniques outlined below can deliver marginal performance gains or represent better coding practices that experienced developers naturally adopt. Evaluating STL Function Overhead Many STL operations carry hidden costs that accumulate during execution. Consider the following approaches for it ...

Posted on Tue, 13 Oct 2026 16:15:34 +0000 by phwae

Calculating Minimum Delivery Path in a Tree Network

The problem presents a scenario involving a delivery network modeled as a tree structure. The network consists of N nodes (locations) connected by N-1 bidirectional roads, with no cycles. One specific node serves as the root (the delivery station). The goal is to determine the minimum distance required to visit all currently active delivery loc ...

Posted on Tue, 13 Oct 2026 16:13:22 +0000 by peppino

C++ Binary Tree Operations: Constructing Max Tree, Merging Trees, Searching BST, and Validating BST

Constructing a Maximum Binary Tree For constructing binary tree problems, pre-order traversal is always used because it visits the root first, allowing us to build left and right subtrees after initializing the root. The core idea is to repeated find the maximum value in the current array range as the subtree root, then recursively construct le ...

Posted on Mon, 12 Oct 2026 16:35:03 +0000 by AjithTV

Maximizing Student Recommendations Based on Exam Scores and PAT Participation

After the "Ladder Competition" (天梯赛), a company's human resources department requested a list of outstanding student recommendations from the organizing committee. This task was assigned to "Jingjing-jie" (静静姐). The company's recommendation process follows these criteria: Only students scoring 175 or above in the Ladd ...

Posted on Mon, 12 Oct 2026 16:07:22 +0000 by gbow

Finding the Longest Common Prefix in an Array of Strings Using C++

Determine the longest common prefix among a collection of strings. If no common prefix exists, return an emppty string "". Examples: Example 1: Input: strings = ["flower","flow","flight"] Output: "fl" Example 2: Input: strings = ["dog","racecar","car"] Output: &quo ...

Posted on Sun, 11 Oct 2026 16:42:31 +0000 by ganeshasri

Implementing Hash Tables and String Rolling Hashes in C++

A hash table delivers expected O(1) time complexity for data retrieval and insertion by mapping arbitrary keys into a fixed-size array. This technique compresses a large key space (e.g., integers up to 10^9) into a manageable index range (typically 10^5 to 10^6). Unlike discretization, which preserves relative order, hashing focuses solely on e ...

Posted on Sat, 10 Oct 2026 16:07:28 +0000 by colake

SMU 2024 Spring Ladder Contest 3 Solutions

7-1 Important Words Repeated Thrice Print the given phrase three times. I'm gonna WIN! I'm gonna WIN! I'm gonna WIN! 7-2 Learning C in Two Hours Given total pages n, pages learned per hour k, and hours m, compute remaining pages. The result cannot be negative. #include <bits/stdc++.h> using namespace std; using i64 = long long; int mai ...

Posted on Fri, 09 Oct 2026 16:25:31 +0000 by unxposed

Understanding C++ Fundamental Data Types and Type Conversions

Arithmetic types in C++ are categorized by size, signedness, and precision. When performing floating-point calculations, prefer double over float: it offers greater precision with negligible performance cost on modern hardware. Size Guarantees and Relationships The standard enforces minimum widths but allows implementations flexibility: short ...

Posted on Thu, 08 Oct 2026 16:42:48 +0000 by madonnazz